Row Size System Limit

[piglet]

Hello,

I was reading over the SQL Reference Manual and noticed that there is a hard limit of 32 MB of data for a table row while we can have up to 1600 columns per table.

Does that 32 MB limit the number or columns? That is can we only have 516 VARCHAR(65000) columns?

516 * 65000 = 33540000 bytes = 32 MB.

Just curious

[id10t]

Hi!

You are right - if you have CHAR(65536) columns only so you can define max 512 columns.

PS:

Code: Select all

2^16 = 65536
2^9 = 512
1MB = 1024^2 = 1048576 Bytes
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(65536 * 512) / 1048576 = (2^16 * 2^9) / 2^20 = 2^25 / 2^20 =  2^5 = 32